Localization:

Adapting a product to local and regional market called localization.

Sometimes it is referred as l10n.

A characteristics of development and testing related to the translation of the software (product) and its content to the end user.

• This includes choosing appropriate symbols, graphics and  cultural consideration in a software program(product).

Goal of localization is : Appropriate linguistic and cultural aspects.

• It is performed by translators, localizers, language engineers or experts.

Internationalization:

Developing a (software) product in such a way that it will be easy to adapt it in other markets(languages and cultures).

Some people refer this as globalization.

A characteristics of development and testing related to handling foreign text and data within a software program

Goal of internationalization: Reduce the middle layer to rewrite the original program in different variants.

• It is carried out by  software development with localization.
• Handling foreign text and data with a program.
• Correct conversion of desired data according to the respective location like handling of currency and data and time formats.
• It also comprise the job of detaching(strings) user interface text from the origin code.